A U.S. naval strike force led by an aircraft carrier was in Middle Eastern waters Tuesday as Iran vowed to hit back against any strike and President Donald Trump said he believed the Islamic republic still wanted talks.
Washington has not ruled out new military intervention against Tehran over its crackdown on protests, which according to rights groups saw thousands of people killed within days.
A strike group led by the USS Abraham Lincoln has now arrived in Middle Eastern waters, US Central Command said, without revealing its precise location.
Since Iran earlier this month launched the crackdown on protests accompanied by a blanket internet blackout, Trump has given mixed signals on intervention which some opponents of the clerical leadership see as the only way to bring about change.
"We have a big armada next to Iran. Bigger than Venezuela," Trump told the Axios, weeks after U.S. military action resulted in the capture of the Latin American nation's president Nicolas Maduro.
But he added: "They want to make a deal. I know so. They called on numerous occasions. They want to talk."
Axios said Trump declined to discuss the options presented to him by his national security team, or which one he prefers.
Analysts say options include strikes on military facilities or targeted hits against the leadership under Ayatollah Ali Khamenei in a full-scale bid to bring down the system that has ruled Iran since the 1979 Islamic revolution that ousted the shah.
The New York Times, meanwhile, reported that Trump has received multiple U.S. intelligence reports "indicating that the Iranian government's position is weakening" and signalling its hold on power "is at its weakest point" since the shah's fall.
Sen. Lindsey Graham, R-S.C., told the paper he had spoken with Trump in recent days about Iran and that "the goal is to end the regime."
"They may stop killing them today, but if they're in charge next month, they'll kill them then," he added.
Iranian officials have over the past days appeared wary of pouring oil on the fire.
Tehran has in the past said a channel of communication is open between Iranian Foreign Minister Abbas Araghchi and U.S. envoy Steve Witkoff, despite the lack of diplomatic relations between the two foes.
But the Hamshahri conservative newspaper Tuesday quoted Revolutionary Guards spokesman Mohammad Ali Naini as saying that "if their aircraft carrier made a mistake and entered Iranian territorial waters, it would be targeted."
The conservative Javan newspaper said Iran was "ready for a major response" and would seize the strategic Strait of Hormuz, a key transit hub for energy supplies.
Meanwhile, an anti-U.S. billboard has appeared in Tehran that appears to show an American aircraft carrier being destroyed.
Rights groups have described the crackdown as the deadliest ever against protests in Iran and warn compiling tolls has been complicated by an almost three-week internet blackout they say is aimed at masking the extent of the repression.
The U.S.-based Human Rights Activists News Agency (HRANA) said it had confirmed 6,126 people had been killed, including 5,777 protesters, 86 minors, 214 members of the security forces and 49 bystanders.
But the group, which has an extensive network of sources inside Iran and has tracked the protests on a daily basis since they began, added it was still investigating another 17,091 possible fatalities.
At least 41,880 people have been arrested, it said.
"Security agencies continue to pursue an approach centred on mass arrests, intimidation, and control of the narrative," HRANA said.
Activists have accused authorities of raiding hospitals to find injured protesters and then arresting them. The health ministry has said all people should present themselves at hospital without worry and not treat themselves at home.
Over the weekend, Persian-language TV channel Iran International, which is based outside Iran, said more than 36,500 Iranians were killed by security forces between January 8 and 9, citing reports, documents and sources.
It was not immediately possible to verify the report.